import time

time.sleep(0.1) # Wait for USB to become ready

from machine import Pin, time_pulse_us, PWM
import utime
import sys

time.sleep(0.1)

# LED Init
#Test for the code can run initially
#Pico LED
led = Pin("LED", Pin.OUT)
led.value(1)
time.sleep(0.5)
led.value(0)

# External LED on GP28 to know the code can run
#Samuel u can remove this untill
led = Pin(28, Pin.OUT)
led.value(True)
time.sleep(1)
led.value(False)
time.sleep(1)
#here in the final program

print("System Ready")

# Define car in each slot
areaa = ["DEA69", "DAD6969", "DBE6969", "DDB6969"]
areab = ['JUG6969', 'USM1069', 'DAV1869']

# Ultrasonic pins
# Define GPIO pins for the ultrasonic sensor (adjust these if you used different pins)
TRIGGER_PIN = 3
ECHO_PIN = 2
trigger = Pin(TRIGGER_PIN, Pin.OUT)
echo = Pin(ECHO_PIN, Pin.IN)

# PIR Sensor on GP15
# Define GPIO pins for the pir (adjust these if you used different pins)
pir = Pin(15, Pin.IN)

# Servo motor
# Define GPIO pins for the servo motor (adjust these if you used different pins)
servo_pin = Pin(19)
pwm = PWM(servo_pin)

# Set Duty Cycle for Different Angles
max_duty = 7864 # 180degrees=Nou Used by us
min_duty = 1802 # Open=0degrees---use this for open
close_duty = 5000 # close=90degrees---use this for close
pwm.freq(50) # Set PWM frequency-pwm.freq(frequency value)

# Start with gate CLOSED
pwm.duty_u16(close_duty)
time.sleep(2)

# Function to detect PIR car-passed event
def get_car_passed():
    """
    Reads PIR sensor.
    PIR HIGH (1) means motion detected.
    PIR LOW (0) means no motion.
    """
    return pir.value() == 0

# Ultrasonic distance detection
def get_car_sensor():
    def get_distance():
        trigger.low()
        utime.sleep_us(2)

        trigger.high()
        utime.sleep_us(10)
        trigger.low()

        try:
            duration = time_pulse_us(echo, 1, 30000)
            if duration < 0:
                return -1

            distance = (duration * 0.0343) / 2
            return distance

        except OSError as e:
            print("Sensor error:", e)
            return -1

    while True:
        dist = get_distance()
        if dist >= 0:
            if dist < 20:
                return True
            else:
                return False

        utime.sleep(0.5)

# MAIN LOOP
while True:
    cs = get_car_sensor()
    if cs == True:
        car_plate = input("Enter plate number: ")
        print("Your car plate number is " + car_plate)

        if car_plate == "stop":
            car_sensor = False

        if car_plate in areaa:
            lista = True
            listb = False
        elif car_plate in areab:
            listb = True
            lista = False
        else:
            lista = False
            listb = False

        if lista == True:
            print("Access Granted, Welcome to Parking Area A")
            pwm.duty_u16(min_duty)   # gate open
            time.sleep(1)

        elif listb == True:
            print("Access Granted, Welcome to Parking Area B")
            pwm.duty_u16(min_duty)   # gate open
            time.sleep(1)

        else:
            print("Access Denied Unidentified Car Plate Number")
            pwm.duty_u16(close_duty)  # keep gate closed
            time.sleep(2)
            continue   # restart loop (no gate movement)

        # Now detect PIR for car passing
        print("Waiting for PIR sensor to detect car passing...")

        while True:
            car_passed = get_car_passed()
            if car_passed:
                print("Car has passed the gate.")
                break
            time.sleep(0.1)
            continue # restart loop ( car still at the gate)

        # After PIR detects passing → close gate
        pwm.duty_u16(close_duty)
        time.sleep(2)

    else:
        # No car detected by ultrasonic → keep gate closed
        pwm.duty_u16(close_duty)
        time.sleep(2)

time.sleep(2)